Fluorescent probes for the detection of magnesium ions (Mg2+): from design to application

Magnesium ions (Mg²⁺) play essential roles in various physiological and pathological processes, its abnormal homeostasis in cells is related to many diseases, such as diabetes, neuromuscular disorders, hypertension and other cardiovascular disorders. Investigation on the regulation of magnesium in cellular processes has attracted considerable interest in the past several decades. Among those reported strategies, fluorescent imaging technology has become a powerful and cost-effective tool for the real-time monitoring of magnesium distribution, uptake and trafficking, due to its superior features of high sensitivity and non-invasiveness, as well as excellent spatial and temporal fidelity. Herein, we critically summarize the progresses in the intracellular magnesium detection with fluorescent imaging probes. Our discussion focuses on the recent contributions concerning fluorescent imaging probes for mapping magnesium in biological processes. All the candidates are organized according to their acceptor structures. The sensing mechanisms of fluorescent probes are also highly taken into account. Challenges, trends and prospects of fluorescent imaging technology in magnesium detection are also set forth.

Herein, progress in intracellular magnesium detection with fluorescent probes is critically summarized in this work.     

Comparing yield estimates derived from LiDAR and aerial photogrammetric point-cloud data with cut-to-length harvester data in a Pinus radiata plantation in Tasmania

Accurate mapping of timber resources in commercial forestry is essential to support planning and management operations of forest growers. Over the last two decades, Light Detection and Ranging (LiDAR) systems have been successfully deployed for the collection of point-cloud data for accurate modelling of forest attributes that are traditionally obtained from plot-based inventory. In recent years, studies conducted in North America and Scandinavia have shown that three-dimensional point clouds derived from digital aerial photogrammetric (AP) data can be used to model forest attributes with a level of accuracy similar to traditional LiDAR-based approaches. A comparative analysis of the performance of the two point-cloud technologies has never been attempted in Australian plantations. In this study, we compared the performance of LiDAR-based and AP-based point clouds for estimating total recoverable volume in a Pinus radiata plantation at Springfield in north-eastern Tasmania, using volume data collected by harvesting machines as a reference. Our results showed that AP point clouds can be used for mapping total recoverable volume in P. radiata plantations with levels of accuracy that are comparable to LiDAR-based estimates. Plot-level relative root mean squared error (RMSE%) values were 23.85% for LiDAR and ranged from 22.07% to 27.10% for the three AP dense point-cloud settings evaluated. At the stand level, RMSE% decreased to 9.86% and 8.91% for LiDAR and AP, respectively. Both LiDAR-based and AP-based modelled volumes showed a close agreement with volumes measured using harvester head data, demonstrating the potential of AP technology for the management and planning of forestry operations in softwood plantations.     

Large-scale synthesis and luminescence of GdPO4 hollow microspheres

GdPO₄ hollow microspheres were synthesized by using a novel multi-step transformation synthetic route for the first time with polystyrene (PS) spheres as the template, followed by the combination of a facile homogeneous precipitation method, an ion-exchange process, and a calcination process. The XRD results indicated that the GdPO₄ hollow microspheres have a pure hexagonal phase. The SEM and TEM images confirmed that the as-obtained GdPO₄ hollow spheres have a uniform morphology with an average diameter of 2.7 μm and shell thickness of about 150 nm. The up-conversion luminescence properties as well as the emission mechanisms of the GdPO₄:Yb³⁺, Ln³⁺ (Ln³⁺ = Tm³⁺, Er³⁺ and Ho³⁺) hollow microspheres were systematically investigated, which show blue (Tm³⁺, ¹G₄ → ³H₆), green (Er³⁺, ⁴S_3/2, ²H_11/2 → ⁴I_15/2), and red (Ho³⁺, ⁵F₅ → ⁵I₈) luminescence under 980 nm NIR excitation, providing potential applications in bioanalysis, optoelectronic and nanoscale devices, future color displays and light-emitting devices, and so on.

GdPO₄ hollow microspheres were synthesized by using a novel multi-step route for the first time with polystyrene (PS) spheres as the template, followed by the combination of a facile homogeneous precipitation method, an ion-exchange process, and a calcination process.     

Low-cost CoFe2O4/biomass carbon hybrid from metal-enriched sulfate reducing bacteria as an electrocatalyst for water oxidation

The development of electrocatalysts for the Oxygen Evolution Reaction (OER) requires extensive and challenging research for the water splitting and fuel cell applications. Herein, we report a low-cost CoFe₂O₄/biomass carbon (CFO@BC/Zn) hybrid from Co-enriched Sulfate Reducing Bacteria (Co-SRB) as an electrocatalyst for OER. The electrocatalyst exhibits a low potential of 1.53 V at a current density 10 mA cm⁻² and Tafel slope of 86 mV dec⁻¹. This method does not require high-cost or long periods of preparation. The density-functional theory (DFT) calculations show a small barrier for oxygen conversion on Fe³⁺ of CFO (100) surface. The synthesis of CFO@BC/Zn may be a new approach for obtaining low-priced electrocatalysts for OER.

A low-cost CoFe₂O₄/biomass carbon (CFO@BC/Zn) hybrid from Co-enriched Sulfate Reducing Bacteria (Co-SRB) as an electrocatalyst for OER. The electrocatalyst exhibits a low potential of 1.53 V at a current density 10 mA cm⁻² and Tafel slope of 86 mV dec⁻¹.     

Lignans from Schisandra chinensis ameliorate cognition deficits and attenuate brain oxidative damage induced by D-galactose in rats

The aim of this study was to explore the neuroprotective effects of active compounds from Schisandra chinensis (Trucz.) Baill. (Magnoliaceae) against the D-galactose (D-gal)-induced neurotoxicity in rat. The Wistar rats were subcutaneously injected with D-gal (150 mg/(kg day)) for six weeks and orally administered with water extract or 95 % ethanol extract (partitioned with petroleum ether (PE), chloroform (CF), ethyl acetate (EA) and n-Butanol (NB), respectively) of the fruits of Schisandra chinensis simultaneously. The alteration of cognitive functions was assessed by using Morris water maze and Step-down type passive avoidance test. The results demonstrated that PE fraction was the most effective fraction to ameliorate cognitive deficits. Further biochemical examination indicated that PE could attenuate the activities decreasing of superoxide dismutase (SOD), catalase (CAT), the total antioxidant (T-AOC) induced by D-gal, and maintain the normal levels of glutathione (GSH), malondialdehyde (MDA) and nitric oxide (NO) in the serum, prefrontal cortex, striatum and hippocampus of the brain of related rat, selectively. Meanwhile, the compounds of PE fraction were also identified as mainly lignans, thus, these results suggest that lignans from the PE fraction of Schisandra chinensis represented a potential source of medicine for the treatment of the aging-associated neurodegenerative diseases.